Hi Rod,
You sum it up well.
I guess it's that many arrogant people take the view that they can only prove that they are right by proving that everyone else is wrong. (even the people that were on their side).

Innately I think that everyone can sense the difference
(That's why we are attracted to some people, BUT want to shove others under a bus)

But it took a sharp cookie like you to actually quantify and put it into words.